CN104707559A

CN104707559A - Aluminum ion doped zinc oxide adsorbent (AZO) as well as preparation method and application thereof

Info

Publication number: CN104707559A
Application number: CN201510087649.6A
Authority: CN
Inventors: 孙小华; 罗伟龙
Original assignee: China Three Gorges University CTGU
Current assignee: China Three Gorges University CTGU
Priority date: 2015-02-26
Filing date: 2015-02-26
Publication date: 2015-06-17

Abstract

The invention discloses a preparation method of a porous flaky structured AZO adsorbent. The preparation method comprises the following steps: dissolving aluminum nitrate enneahydrate into a zinc solution, adding a hexamethylene tetramine (HMTA) solution, and uniformly stirring to implement hydrothermal reaction; putting the precursor obtained through reaction into a muffle furnace for calcination, thereby finally obtaining porous flaky AZO powder. According to the preparation method, the specific surface area of the adsorbent is increased through calcination, and the electrical property of the surface of the adsorbent is improved through aluminum ion doping, so that the adsorption property of the adsorbent to dye is improved. The porous flaky structured AZO adsorbent prepared by using the preparation method has the advantages of simple preparation process, stable property, efficient adsorption efficiency, no toxicity and the like, can be used for removing organic pollutants, and can be applied to the photocatalysis field.

Description

A kind of Al-doping zinc oxide adsorbent (AZO), preparation method and application thereof

technical field:

The present invention relates to a kind of preparation method of porous flake AZO adsorbent, for efficient adsorption organic dyestuff methyl orange and photocatalysis field.

background technology:

Methyl orange is a kind of organic dyestuff.Organic dyestuff is widely used in the industrial circles such as weaving, papermaking, cosmetics, plastics, although promoted expanding economy, a large amount of waste water from dyestuff produced have a strong impact on the life of the health of these mankind.Therefore, one of study hotspot improvement of waste water from dyestuff being become to environmental administration and research worker.

The method of conventional improvement waste water mainly comprises: membrane separation process, biological degradation method, photocatalytic oxidation, the precipitation method.These methods in processing procedure owing to reducing dye content limited in one's ability or causing the problems such as secondary pollution, operating process complexity is loaded down with trivial details, cost is higher due to harmful by-products in processing procedure.Adopt which kind of method can avoid the existence of the problems referred to above, the effect of waste water treatment can be reached again, make more researcher be devoted to the research and development of novel process.And absorption method is as simple to operate, safety non-toxic, is more and more subject to certainly advantages such as the adsorption rate of dyestuff are high.It mainly comprises physical absorption, chemisorbed two type.The former adsorption capacity is mainly reflected in large, the suitable pore size of the specific area of adsorbent, and the latter is mainly because its surface has a large amount of functional groups, is reached the effect of absorption by the effect of the bonding force with dye molecule.Certainly in chemisorbed process, often also relate to the existence of physical absorption.

Zinc oxide has stronger Antiradiation injury ability, and be the material of extensive use, it has very high heat endurance and chemical stability.The present invention adopts the zinc oxide of water heat transfer laminated structure, and form loose structure by calcining manners and increase its specific area and simple metal ion mixing mode and change the electrical of zinc oxide surface, both improve its adsorption capacity to methyl orange jointly.Experiment condition needed for the method is gentle, simple to operation, the powder of preparation has that powder thin (nanoscale), purity are high, good dispersion, evenly, the feature such as good, the controlled shape of narrowly distributing, crystal formation.

summary of the invention:

The object of this invention is to provide a kind of preparation method of porous laminated structure AZO adsorbent, the AZO that the method is prepared realizes the efficient adsorption process to methyl orange, effectively improves water body environment.Its technique is simple, cost is low, favorable repeatability, can apply to the removal of organic pollution, and can be used in photocatalysis field.

Technical solution of the present invention: with controlling hydro-thermal and calcine technology, prepare a kind of porous laminated structure AZO adsorbent.Step is:

Step one: appropriate ANN aluminium nitrate nonahydrate is dissolved in certain density zinc salt solution, then add certain density hexa (HMTA) aqueous solution, consistent stirs 10 minutes;

Step 2: solution step one prepared is transferred in 50mL water heating kettle, carries out hydro-thermal reaction;

Step 3: the product cleaning after hydro-thermal reaction is clean, drying obtains presoma, then puts it in Muffle furnace and calcines, finally obtains porous flake AZO powder.

Zinc salt in above-mentioned steps one is zinc nitrate hexahydrate or zinc acetate or zinc sulfate; ANN aluminium nitrate nonahydrate concentration is in the solution 1mM ~ 5mM; Zinc salt concentration is 8mM ~ 12mM; The concentration of HMTA is 8mM ~ 12mM.

The hydrothermal temperature of above-mentioned steps two is 120 ~ 180 DEG C, and the time is 12 ~ 24h.

In above-mentioned steps three, calcining heat is 300 ~ 600 ° of C, and the time is 1 ~ 3h.

advantage of the present invention is:

In this technique, hydrothermal temperature is at 120 ~ 180 DEG C, and reaction temperature is low; Control the synthesis and structure pattern of product well.And AZO prepared by the method has significant adsorption capacity to methyl orange.The preparation technology of this invention is simple to operation, reproducible and need the simple cost compare of equipment low; The performance of the adsorbent of preparation is excellent.

Accompanying drawing explanation

Fig. 1 is the SEM of the presoma of sheet ZnO.

Fig. 2 is the SEM of porous flake ZnO.

Fig. 3 is the presoma SEM of sheet AZO.

Fig. 4 is the SEM of porous flake AZO.

Fig. 5 is ZnO, AZO absorption (C/C to MO ₀-t).Interior illustration is that AZO is to the absorption photo of MO at different time.

Fig. 6 is that ZnO, AZO are under ultraviolet light to the photocatalysis (C/C of MO ₀-t).

detailed description of the invention:

embodiment 1

the presoma of sheet ZnO

Configuration 10mM Zn (NO) ₃.6H ₂o solution, then adds HMTA, and make the concentration of HMTA be 8mM ~ 12mM, then consistent stirs 10 minutes; Be transferred to by the solution prepared in 50mL water heating kettle, carry out hydro-thermal reaction, reaction temperature is 120 ~ 180 DEG C, and the time is 12 ~ 24h, treats that nature cools; By the presoma powder that the product cleaning after hydro-thermal reaction is clean, drying obtains sheet ZnO.Fig. 1 is the SEM of the presoma of sheet ZnO, and powder presents fine and close laminated structure.

embodiment 2

porous flake ZnO

Configuration 10mM Zn(NO) ₃.6H ₂o solution, then adds HMTA, and make the concentration of HMTA be 8mM ~ 12mM, then consistent stirs 10 minutes; Be transferred to by the solution prepared in 50mL water heating kettle, carry out hydro-thermal reaction, reaction temperature is 120 ~ 180 DEG C, and the time is 12 ~ 24h, treats that nature cools; Product cleaning after hydro-thermal reaction is clean, drying obtains presoma.Presoma be raised to 400 DEG C with the heating rate of 4 DEG C/min in Muffle furnace and be incubated 1h, treating Temperature fall, obtaining porous flake AZO powder.Fig. 2 is the SEM of porous flake ZnO, mushy sheet-like morphology that powder is, and sheet is assembled by little nano particle.Fig. 5 is ZnO, AZO absorption C/C to MO ₀-t.Interior illustration is that AZO is to the absorption photo of MO at different time.In figure, black line is that ZnO changes the adsorption concentration of MO, can find out to occur adsorption equilibrium after 15min, and adsorption rate is about 25%.Fig. 6 is that ZnO, AZO are under ultraviolet light to the photocatalysis (C/C of MO ₀-t).In figure black line be ZnO under ultraviolet light to the photocatalysis of MO, can find out that illumination 60min degradation rate is close to 20%.

embodiment 3

the presoma of sheet AZO

Configuration 10mM Zn(NO) ₃.6H ₂o solution, then adds HMTA, Al (NO ₃) ₃.9H ₂o, makes HMTA and Al (NO ₃) ₃.9H ₂the concentration of O is respectively 8mM ~ 12mM, 1mM ~ 5mM, and then consistent stirs 10 minutes; Be transferred to by the solution prepared in 50mL water heating kettle, carry out hydro-thermal reaction, reaction temperature is 120 ~ 180 DEG C, and the time is 12 ~ 24h, treats that nature cools; By the presoma that the product cleaning after hydro-thermal reaction is clean, drying obtains sheet AZO.Fig. 3 is the presoma SEM of sheet AZO, and powder is fine and close laminated structure.

embodiment 4

porous flake AZO

Configuration 10mM Zn(NO) ₃6H ₂o solution, then adds HMTA, Al (NO ₃) ₃.9H ₂o, makes HMTA and Al (NO ₃) ₃9H ₂the concentration of O is respectively 8mM ~ 12mM, 1mM ~ 5mM, and then consistent stirs 10 minutes; Be transferred to by the solution prepared in 50mL water heating kettle, carry out hydro-thermal reaction, reaction temperature is 120 ~ 180 DEG C, and the time is 12 ~ 24h, treats that nature cools; Product cleaning after hydro-thermal reaction is clean, drying obtains presoma, presoma is raised to 400 DEG C with the heating rate of 4 DEG C/min in Muffle furnace and is incubated 1h, treating Temperature fall, obtaining porous flake AZO powder.Fig. 4 is the SEM of porous flake AZO, and mushy sheet-like morphology that powder is and sheet are assembled by little nano particle.Fig. 5 is ZnO, AZO absorption C/C to MO ₀-t.Interior illustration is that AZO is to the absorption photo of MO at different time.In figure, red line is that AZO changes the adsorption concentration of MO, can find out to occur adsorption equilibrium after 5min, and adsorption rate is 100%.Can find out absorption 1min from interior illustration after, MO solution is transparent, is substantially adsorbed completely.Fig. 6 is that ZnO, AZO are under ultraviolet light to the photocatalysis (C/C of MO ₀-t).In figure red line be AZO under ultraviolet light to the photocatalysis of MO, can find out that illumination 15min degradation rate is close to 100%.

Claims

1. an Al-doping zinc oxide adsorbent (AZO), is characterized in that, the surface band electropositive of this adsorbent and porous laminated structure.

2. a preparation method for Al-doping zinc oxide adsorbent (AZO), is characterized in that, comprise the steps:

1) be dissolved in zinc salt solution by ANN aluminium nitrate nonahydrate, then add hexa (HMTA) aqueous solution, Keep agitation 10 minutes, makes it even;

2) solution that step 1) prepares is transferred in 50mL water heating kettle, hydro-thermal reaction 12-24h at 120 ~ 180 DEG C;

3) by step 2) product cleaning after hydro-thermal reaction is clean, drying obtains presoma, and then put it in Muffle furnace and calcine 1 ~ 3h at 300 ~ 600 DEG C, obtain the AZO powder of porous laminated structure.

3. the preparation method of Al-doping zinc oxide adsorbent (AZO) according to claim 2, is characterized in that, ANN aluminium nitrate nonahydrate concentration is in the solution 1mM ~ 5mM; Described zinc salt concentration is 8mM ~ 12mM, and zinc salt is zinc nitrate hexahydrate or zinc acetate or zinc sulfate; The concentration of HMTA is 8mM ~ 12mM.

4. any one of claim 1-3 Al-doping zinc oxide adsorbent (AZO) is administering the application on toxic organic pollutant.

5. any one of claim 1-3 Al-doping zinc oxide adsorbent (AZO) application on photocatalysis reagent.